MHT CET2019Morning ShiftMathematicsIndefinite IntegrationActual
If ∫ 1 1 - c o t x d x = A x + B l o g s i n x - c o s x + c then A + B = …
Options
- A1
- B– 1
- C0
- D– 2
Correct answer
A. 1
Step-by-step solution
Let l = ∫ 1 1 - c o t x d x = ∫ 1 1 - c o s x s i n x d x = ∫ s i n x s i n x - c o s x d x = 1 2 ∫ 2 s i n x s i n x - c o s x d x = 1 2 ∫ s i n x + s i n x + c o s x - c o s x s i n x - c o s x d x = 1 2 ∫ s i n x + c o s x + s i n x - c o s x s i n x - c o s x d x = 1 2 [ ∫ d x + ∫ s i n x + c o s x s i n x - c o s x d x Let s i n x - c o s x = t ⇒ c o s x + s i n x d x = d t ∴ l = 1 2 ∫ d x + ∫ 1 t d t = 1 2 x + log t + C = 1 2 x + log s i n x - c o s x + C = x 2 + 1 2 log s i n x - c o s x + C Here